Ilmor Thermostat Housing O-Ring

This Thermostat Housing O-Ring is used with both the 170* and 190* thermostats from Ilmor. Replace this O-Ring every time you remove and replace your thermostat. Fits all 5.7L, 5.7L OPS, 6.0L, 6.0L OPS, 6.2L, and 6.2L OPS engines.